The tree house lands in Wild West America but there's no one around. Has it landed in a ghost town? When a gang of nasty horse thieves gallop past it's not long before Jack & Annie are swept up in another adventure. With their new cowboy friend Slim they set out across the prairie to rescue Slim's mare from the horse thieves. But Jack & Annie still have their next riddle to solve. Will the spooky ghost be any help?